Isokinetic rotator cuff strength ratios in overhead athletes
In this review, the authors found evidence of a lower functional deceleration ratio (FDR, eccentric external rotation/concentric internal rotation) in overhead athletes, mostly driven by an increase in internal rotation power. Despite this, there was no consensus about which exercise program is more effective regarding the correction of this ratio.
Overhead sports place great stress on the shoulder due to the repetitive throwing motion. Imbalances in rotator cuff (RC) strength are thought to increase injury risk by placing excessive stress on passive stabilizers.
Currently, there is no consensus about the optimal shoulder strength ratio or about the potential effect of exercise on it. Thus, the authors aimed to review the literature regarding rotator cuff strength ratios in overhead athletes and how exercise programs influence them.
14 studies looking at RC isokinetic strength in overhead athletes were included in the review. Risk of bias and level of assessment were performed. All studies were classified as a B level of evidence.
The review showed evidence of increased internal rotation in the dominant shoulder. FDR values ranged from 0.46 to 1.05. Data regarding the effect of exercise on the FDR did not allow for a consensus to be achieved about which parameters have a beneficial effect.
> From: Berckmans et al., Phys Ther Sport 27 (2017) 65-75(Epub ahead of print). All rights reserved to Elsevier Inc.. Click here for the online summary.